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Black Hole Information Loss Paradox Solution Proposed
Anuborn Satirak writes to tell us that Physicists from Case Western Reserve University claim to have cracked the black hole information loss paradox that has puzzled physicists for the past 40 years. "The physicists are quick to assure astronomers and astrophysicists that what is observed in gravity pulling masses together still holds true, but what is controversial about the new finding is that 'from an external viewer's point it takes an infinite amount of time to form an event horizon and that the clock for the objects falling into the black hole appears to slow down to zero,' said Krauss, director of Case's Center for Education and Research in Cosmology."
It's what happens in the physical world when you divide by zero.
This signature is a waste of 42 characters
Of course that's true, but is it also the case that a black hole can hold a stargate open, slowly sucking all of the surrounding area around the other gate into its time dilation bubble? Really, as a taxpayer funding this research, I want answers.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
Here's the preprint.
I came here for a good argument
Are they saying black holes are perpetually in the creation phase, or they just don't exist at all unless they formed at the beginning of time?
from an external viewer's point it takes an infinite amount of time to form an event horizon
Nothing like an experiment to verify theories. And indeed, a quick trip to the DMV or the social security office confirms that it does seem to take an infinite amount of time for any event to occur, and that the clock seems to stop locally.
See? no need for black holes.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Anyone know what happened to Hawking's proposal for information loss?
o n_paradox
Basically what Hawking said (in a late essay entry in a science conference) was that Black Holes do 'digest' information and therefore you have information loss, however (and this is where his proposal was a bit controversial) Hawking suggested that the conglomeration of parallel universes will have a particular Black Hole present in one, and the same Black Hole missing in another, therefore the TOTAL information for ALL Universes, is retained.
Here's a link to Hawking's Black Hole Paradox: http://en.wikipedia.org/wiki/Black_hole_informati
And from the wiki article, here's the line I'm mentioning in my post:
"...On October 28, 2006, The Discovery Channel aired a show called "The Hawking Paradox". The show explained Hawking's conclusion that one must look at the universe as a whole, and that information lost in black holes is saved in parallel universes where no black holes exist."
It seems that this new solution is completely disregarding Hawking's proposal and replacing it with a new, stretched solution.
A black cat crossing your path signifies that the animal is going somewhere. -- Groucho Marx
A Slashdotter would realize that if you don't want to see any information, you need to view the event horizon with a threshold of -1.
Firstly, they emphasize in their paper that they are considering their problem from the point of view of an external observer, rather than the point of view of an observer falling into the black hole. They write: They also contrast their results with previously accepted analysis of black hole formation: So, in essence, they are presenting findings that suggest that even quantum effects are taken into account, the collapse takes an infinite amount of time. This is signficant because it means that while the collapsing mass can appear to get closer and closer to being a singularity, it can never really achieve this final state to an external observer. How this relates to information loss is then described: So, in essence, the collapse of the black hole takes an infinite amount of time, during which time the black hole will evaporate via Hawking radiation. So objects falling into a black hole will never actually be swallowed up into the black hole (though they will get arbitrarily close and arbitrarily crushed!). Since the collapse is never really complete, information about the objects is never entirely lost. The emitted radiation will thus contain 'information' about the infalling objects. This in some way can be seen to resolve the seeming information paradox, whereby black holes were seemingly able to 'swallow up' information and completely destroy it (whereas no other process in the universe appeared able to do so).
There is an article about this same thing in new scientistb lack-holes-really-exist.html
http://space.newscientist.com/article/dn12089-do-
It quotes 't Hooft as claiming that "The process he describes can in no way produce enough radiation to make a black hole disappear as quickly as he is suggesting." So I am skeptical.
we haven't (seen any black holes). You can't "see" a black hole (that's why they're named as they are). We have observed the effects of things which match our expectation of the effects a black hole would cause. I assume the authors of this paper explain how their black-hole-like-object-which-isn't-a-black-hole can cause the same effects.
"National Security is the chief cause of national insecurity." - Celine's First Law
No, that's not correct. Normal GR predicts that (in the frame of someone away from the BH) the person falling into the black hole will take an infinite amount of time to reach the event horizon. In GR infinite time isn't the same thing as never! In the frame of the person falling into the BH (the proper time frame,) the faller crosses the event horizon in finite time and hits the center quite quickly (for non-huge black holes). The confusion and controversy lies in the concept of infinite time. Some take it to mean that black holes can't actually form (and must either be primordial or not exist). But infinite time might be a finite distance away due to weirdness with coordinates. An object falling through an event horizon might pass through infinite future and then travel back in time from the infinite future to the current. In the outside viewers frame, there might be two copies of the in-falling person, one inside and one outside. In this scenario, black holes can exist, and can contain the mass of stuff that falls into the hole...before it falls into the hole! Or it could all be bullshit and artifact of a broken theory of gravity.
To my understanding, the suggestion is that the collapsing matter will never create a true event horizon (a boundary from which nothing can ever escape). However this doesn't prevent the matter from collapsing to an arbitrarily high density and creating an increasingly large escape velocity. Think of a dense chunk of matter (but not infinitely dense). It will warp spacetime around it significantly, and it will bend the direction of light rays significantly. If a ray of light strays too close to the center of this quasi-singularity, it will get caught in a tight orbit. Now, the orbit won't be truly stable, and the light ray will, after some rotations around the gravity well, finally escape.
The denser the quasi-singularity is, the more rays will get trapped (temporarily) in these orbits, and the longer they will stay trapped. At a certain point, when light is being trapped for 10E80 year, the object could very sensibly be called a black hole. For all intents and purposes, infalling light does not escape. In principle, in a very long time the light may escape. Or, according to this new theory, the black hole may evaporate before actually forming (although this, too, will take a long time). But the massive curvature of spacetime will still lead to all the light-trapping and time-dilating effects normally predicted for black holes. This theory is merely suggesting that the containment is not absolute. Eventually, the stuff will escape. (Although for material objects, they will have been crushed and distorted beyond recognition. But at least in principle, the 'information' about them wasn't lost.)
Under the new theory, objects of near-infinite density still form, and still (in any practical sense) trap all incoming matter. However the question comes down to whether the singularity at the center is a true singularity with a true event horizon, or a perpetually-collapsing mass that has not quite yet reached the point of being a true black hole.
No. Black holes aren't lopsided
Because if the black hole was big enough to suck in the CERN campus with its gravity, the matter from which it was formed would have the same effect.
Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.
-- http://www.mrc-cbu.cam.ac.uk/~mattd/Cmabrigde/
The unofficial
That's a rather zen question, actually. In some ways it amounts to asking "What's the difference between the matter that forms the black hole, and the matter that is falling into it?" Conventionally, the answer would be: all the matter inside the event horizon is part of the black hole, and everything outside the event horizon is falling into it (or, rather, is being gravitationally attracted towards it, and may or may not actually fall).
If this new bit of theory is correct, then the answer actually becomes harder, because the event horizon never forms, so you can't really say that some matter is inside vs. outside. Of course there is probably a sensible way to define a "pseudo-horizon" based upon a threshold where the probability of light escaping sharply drops towards 0.
I guess another way of thinking about it would be to say that this hypothetical matter that is "at the center of where the black hole is forming" would inevitably be included into the collapsing mass and would thus, itself, become part of the black hole.
It's true that EMR that enters the event horizon cannot escape. The evaporation process, called Hawking radiation, is a quantum effect that has no conventional analogue. Basically, in quantum mechanics (or rather quantum field theory), it is predicted that "virtual particles" randomly appear and disappear all the time. These virtual particles actually carry the force of things like the electric fields, magnetic fields, gravitational fields, etc. (they also avoid 'action at a distance' problems...). So in the vacuum, you will get random particle-antiparticle pairs appearing at random, and annihilating each other a moment later (these constant fluctuations are very important in modern theories, actually). If you imagine one of these random fluctuations occurring right beside an event horizon, you can imagine that one of the two particles gets sucked into the event horizon, but the other one escapes and sails off into the universe. The particle entering the black hole will actually reduce its mass (not increase it, as one would normally expect... though the proof of this requires digging into the math quite a bit), and the particle that escapes thereby carries away some of the mass of the black hole. Thus, over time, the blackhole is basically emitting radiation and slowly 'evaporating.'
Now, I know this idea of "virtual particles" randomly appearing and disappearing sounds totally bizarre. In fact it sounds like pseudo-science or an overcomlicated story that particle physicists are weaving. However these effects do have experimental backing (e.g. Casimir forces).
It turns out the rate of evaporation increases as you decrease in size. So really "micro black holes" (it is predicted that they will be created in upcoming particle accelerators) will evaporate very quickly. Big black holes will evaporate slowly at first, but then faster and faster as they shrink, until they get very small and release the last of their energy, in some sort of burst, yes. However a fundamental, unanswered, question is whether the radiation being emitted by the black hole contains 'information' about the states of things that went into the black hole. No one knows for sure. The conventional answer was that any information that goes into a black hole is lost forever.
However to many scientists, this answer was unsatisfactory.
Over a nice meal.
Reality is fluffy!
That's an interesting viewpoint, but I don't think you understand physics.
QM lies at the physical border of observable physics. At the QM boundary, concepts we take for granted such as electrons and the speed of light have different meaning. Humanity has nothing to do with it. At a small scale, the behavior of matter changes.
Here's an analogy:
Let's say Newtonian (ordinary) physics involves sitting on the side of the road and tracking how fast people are driving in their cars. From this perspective, you can get a pretty good idea where the cars are going. But there's still some randomness to it, if some driver changes their mind.
In this analogy, QM would be like sitting inside each car tracking who is having what conversation, who is on their cellphone, whether their hands are on the gearshift or on their girlfriend's boob, etc. It's a whole other level that you can't see from the side of the road.
If you could be inside each car, then you would know. But you can't. That's QM, the individual decision-making of each driver on the road.
Each driver==each electron. Whether you choose to track electrons with free will or with robotics, it's still too small and random to keep track of all the time.